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15.1 Inlroduction

The implementation ofstatistical process control

Ir 0biectives

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, J r , . ' . r t . .J.Ut, ts. r , . . r . t . . , - . i \ - . r r . . , H,,h. .vr . , r , \ . . , r .1N,rrc. I r ' ! \ t , r r t t , \ r t . , . . . I I I | , , r . , | | . I l )

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. , . r t . . ra . - i r th, . t , r ,of , . . r r( ontru for Brlsifess t-xccIence, rhe ttcse.:rch nn.:t tdLrcation Divisi;r ofr \ . r l l , , r . i ( , rF,r l , r rB I , . . , . , . . l r , , ,v t , , r , , , . r , . ,8, . . . . t i . i , , not u Jr-

Whc('Sl'C nr propert], in use it has bccn shoh.n th.t qualftv_retrtedcosts.afe usLr.rltv kfown afd l()r., rnc:t th.rt dren thc usc ot SpC l{,asspecifie.l bv . cusromc, ar te.rst irliti.l v (.iqucs rrcquenrry (.qui." r.'..', *,np',",, i. *lT,Ll,Til;.T".1i:r::,iiSPC to be of considcrabtc bcncfii

The mp enrentar on 0f stat s l ca p.0cess c0nlro 383

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rn;'nagcrs. Althorgh thcv sometimcs recoprize qujitv .rr'6"ing

.rn:'ipoftant p.rt ot cory{)rate sir.rtcgy, thcv do not apf,ear to knotr. tr,hat.fiectr!e steps to takr in order h) carrv out the st;.teg\. E\r\r n(nI inn)mc orSinizat ions, qui t i tv is sccf is ;n absiract properrv.nrd nor as . lnreasufabi. nnci .on iroltnb t(, pn r.l nretef.I N' , , r .1 nn,. ' r 'h.r t . r . , r r . . . i , . nr . . i , , . r t \ . , r L,ml, . r r , . r t , . , , r l , . r \1. t , , .$ t i r - r r r t , , rn. ,n. , , r . t , , , . r r i . lL, , , . r r , . i , . rh,

t r r r , . , r

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15.2 Successlul users 0l SpC and the beneti tsderived

ln J.pth w(,rk in l , rUini /nrn,rrs Whi,h Lrsc St,( . srctesstLrIr . has gtrcn.1{.rr et r (1( nN lh,r l ( Ust,)nj . r dr iv, ! r In in.rgfmcnt sy\ t ( rns push sLrpl t ( , rslor ' . 'ds lho u! ( ) f p l r ) .ess

. rprbi t i tv . rsscssnrcnis . rn p( tss.r , | t r , , t

Lh.r ls l t nrUst be r ,1\rgrr i r ,c l , t r t r cvcr, r t r . r l cx l ! , f I i l i r ( ,ssu(, , r r ( ikn(x s n( ' t ne. fssrr i l ! k , , rd l { ) rn undfrst . r r r ( t ing () f . i thcf thc \ , r lue ( , t t r ( ,, . i f ! . fce oi t l r . h.hniques

( los(.cx,)nr |n.r i ion ( t ofginizntn),r jn whi .h SI,( . \ \ , rs Used in(( ! |1\1t lhds sh()r ,n th i l th.r( ,$, . rs no r , . r t c(nnnr i inrrr ( r crr .oLrr . rBfDxrt rn,m{f ior m,)n.r t { rncnr. l t * , . r \ . rpp.rn,nr i r r s,)nrt , { ) t th.sc ih.r l t r . ( ( ) rrn1)r ' reLlgc nn( l ( \ eI losi l i ! e dr, f f i t . , rn lc.rd t ( ) unl t ls t i f i r t , t { , c ln inrs n)

r l , , | . , , . - ' , ' , , , r , , . \ , r , r , r r , . . , r r , , , r' , ' t hr t t \ , r r \ r \ i t in. t . , | . , r

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r , . . r , r l \ , , r ' .1 lh, \ i . \ l r , ;1 , , - r . . . , . , , . , 1 . . . , , , , 1 , , ; ,

l .u lv succcsi f l r l us.rs of StC.dn r . ,nrr in sr) ontv rvhcn lhe scnior nr.rn-. rg( 'nrent is both .1 ,arc r i i ind ronmii ted k) ihc conr inucd usc nnLii ' \ ' r , , f

'h rr " ' ,h. r . lu rqr.- - r , , n. , r . , ; , . \ . , , i . . r r , { r . I . r r n. , . r . , ,1,_n' , \nv, , .ur f i I ts . l lur ' r . , ! . r , t r i , , r t i , , t t . r t , , . . , r - . . , t

- t . r h. .F\(r leJb! an enthusi ist ic mcmbcr of t |c managemeni r( : .m.Other themcs r,hich fecur in succ.,ssful uscr orgamzntrcJn

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Top man.rgemeni undersrood vnrjation and rhe inrFortrnce of St,Ckcnnrques to su( cesshrl perfornrnce tmpro\ rment.

xI 384 Stal s l ca Process Contro

.: All thc pcoplc ifrolved in thc useofthe techniqurs understood $41atihey \^,c'rc bcnrg asked io do nnd i{h\' it should hclF them.

; lrainhg, f(,lloxed b,v clear.rnd rvritten instructions on rhe agrcedproccdurcs, tras slstematicnlly intro(tuced .tnd nnlo$,ed up.

Ih.se rcquirernents arc, of colrrse, cortanrcd wiihin ihe gcncral prif-c ip lcs of g(x)d Ltu.r l i tv m.rn.r tcnrcnt.

I hc bor lcf i ts h) bc l ler i |ed f rom thc .ppl icat ion of r rar ist ical metho. is ( ' fpro&ss control are nr.rny irnd !ified. A m,rior spin,off is rh., impro!(,dor( .ont inui l r g rcf uLrtron for c{nrsistent qu.r l i i \ pn)dLrcts or scrYico Thisl ( ' . rds hi . sh adv of . ' \p.rnding, alwnys hcul th\ , , shnfe of thc nl : r rkct , orin]pfoi l . l ef f r ' . t i !cncss/cf f i ( icncy. l ho impr{) \ ' r , ( l pro.r 'ss cofs isk,ncydcr lv. . l . iUs(s n dlrcct rcducl()n rn f \ rcrnr l t r i lnr( , cosr rv i r rantv. l , I r ' . . , . r .1. r ' , r , . , . t l . . r t . . I r l r l , , , . , r . r r , l . , 1, , . . , , ; . . , , .1 s . ,.orrcspond'ng |1\ l ' r . t ion i r r .osts of intonr.r l f . r i lu '1, s.rrp, r1, t r ,ork,w.rst(d l inrr , sc.ondn|. ! or low vi lUe pr(nlLr.r , ch. . gencrnh,s n b(,ruslnr |arsc in pRrlr . l i ! i ty , L) \ , ( \ l r r . ing th. s izf o i rhc 'h ic j ( lcn phr\ t 'whi .h is r l r \ { , I { t lo t fodu. i F n(nr (onl(n ' l r l | r rg pRxlUcts or servnls.

Ih. Er. i t ( r d( grec of fRr css crDtf t r l a l lows rn , ) \ f f . r l l rcdu. i ( ' r in the(hc(king/ insP({t i (nr /ksi ing r l lor ts, ofk j l (sul l ing jn n rc( lu. l i (n orf t r lcplovnr, n l o l srr f f . l lx l r .n( f i ts . r r ( , r r ) t . ,nr l rncd k)I subsr.rnr i , r llo!vcr inB ol to l . r l q( | . r l i t \ , reLrt . { l .osts, I ( ) r Idr l i i i (nr , r l info rnt i ( ! r sufh.rs vend() f f . r t ing . r i lows Inorc ( l f ic i fnt m.rnn8.nr( nt of nrc.rs su.h ispur.hrsir l l t , ( l fs ign, nr . r fLct in l t , rnd e\ fn . r . .oLrnt ing'Itrl, mijor r('qoirc,|nenls lh.n .rPp0nr t,) b. ncccss.rry foi the succtssfrrlinr f l rmcnhlrcnoiSI 'C,nn{ l thfserf t Pfcscrr i in. l l orgrniznt ion s,hrchc(Dt inue n) use th(, tu.hrrk lu.s sLr.cessful lv rn( l r ler i \ ' ( ' the bcncl i is :

l l . , l , . ' r . r I l n. , l . rRi I f , l . r , l . , , . . { t r . rnr \ I , i r r , I r . , ; ' .n i r !2 D.. l i ( .1tcd . rnd $el l inkJrmcd qu. l i tv rc l . r tc. l nr . rnage(s).

I t h.s. lso bi ,en noi .c1 bi , th( ' author and his col leagu. 's thrr rhc inter( \ r t ion of . ' th i fd p.rr t ) ' s l rch . rs a consDitnnt or extrrnal r ra iner hasa vcr) fositlvc effect.

ta 15.3 The implementation ol SPCSrccessful implemcniihon of SPC dcpcnds on the approach to the workbeing structurccl. This applies to all organizntions, .rvlnrcvcr their sjze,technology or product/scrlice range. Uns ccessful SPC inplcnenrationprogramnlcs usually show lvakness.'s $ithin either the sh.uchrre of the

&Ttre mp enre r lat 0n cf s latrs l ca pr0fes\ c0njroi 385 I

p() j .c l or .onrni t lncnl h) i t . An\ pr)c idur. . rdoPhrJ f t \ lLr iR,s (nn| l r t l_rrcnl l r r senior nr. inrgcnx,nr to dr oLr i ( \ t ty. : ( ) t th. t rofk. l r r t .n i l ] ,h{)us. .o drr l i f , r t i r n) b( r f .d i , . r \n i t ibk, fh{r sf t ( \ t i ( r r o l n \Pl , f j r r (p( ! . ( l ( , Lr !n.h th( , i f r r ( r r . t i ( ) . { ) i St ' ( \hoI ld l i t i , . r . . ( j ( |n l ( ) t rh.krr i ) \ \ 'k t r ( ,

. r ! l i l . r )k i fc l t l ) ( , inrpr( i \ .nrcnr {) t l t r ( , t i ( [ ( ,s\ t r . i l l l ri r Shl \ ' ( l .s f , rL ' lL, ;

l \ )ssibk r i lh in.r r ' , rs i r r .b l ( , t i . l , t ( , r i r ! l ;lossihl . L iv lh l U! () t l . (hrr i ( l1| fs r ! l r j r f in l t . , r r , r jLNl. sI I f t r t r , r tnrrr ,r ( i f l l r f r r t r ( ! l r r . l r r r

l l j f l i f : , t l , . r f f i ( r$hi( .hL,surt t \ ih.rs l ( ,hc( j \ .kr j , r j .s t j r r ( j f ! . I r i^ l i ( j , rs\ l lJnrr rsr jJ l r ( r r l . r l r I r j l i ( ) f l ( j ! ( !ntrr . r tnr)r t . ( )Lr tsr( t r l t r , t ( ! i r ) toqLr l, . { l ' r11r" ' I l \ r ) l l r r ( | t ,k!r , : \ { .s l ! r l l r . r t . \ r j ( ) l . r t r ] l . . \ ( t . f r r ( ) | \ , t t j ( , \, , , . t ' r r ( r j I ls \ nr l ) , r1| l . t i ( lo lh( . r t , \1r t i0r j ( j l r f \ t t r j r l t l \ \ ( ! r t nr i I j j I , j l. l r ( )11 . r i r l l inr . l ( j l f i , r j i r r r t n r i r , $. iLI . r L( \ .hn Llrk! , l nr , l r . , ! . r | , . , j1l l r ic , \ r ( . r1r , r1.s l ln i , . rs i ( l , r ( [ r ' t t i r ( )$. . { t$.

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' rs.s s| .h.rs rh () | rL,rr t , ,Nnr l t | , . \ , , r I r r t . , i t , jnr t i l . , ln\ , r fst i l { . . r

l ( i l ( ,1 r \ t f i r !or l ! ' ( f . h( , . r . t 11, , , I r \ ( - .s,r \ 1. , ( i t j r i , \ ' ,h( ! r t ( t | (n t \ , l t ) l. f . r l , \1. r \ lLr t l j f f t rcqrkJrt t \ ( r .LIr , rg s( ,Lr( . r ) t ( l i I t (Lr l r \ . R,t , r l f ( t t ( ,r r ' ( )h edr l , r r ( l t r , r rn i , r ! . i \ ih. . r l ,5( . r j ( . t r ( ) | j1, . I r , r j fL, , I j ( r , | ( r rn j , ) i . r| | r^ ! ] . r l l t , r l )1. . I lhL,s i , js l

. , , , . . , t , 1, , . r ' t , , . - , t . . . . , t . t , . r . t1, . . , t , . , . j r t , . , r . , , t j . t . .

l l r ' l ' , , ' r t \ ' i . \ , , ,1, . , r . . , , . i . t , r . . r t . . , , . t , , . , . . , r , . .L, l l l ,e r . l r , rL.rrrr t bUi.rR. \ r j f t \ nr()R,wi l l i , r i tv r \ ( , i \ . ( l J l r , ( , \p( , r t i { .t , r rh. ' ( (n\Ul t , int ' , $ i r i ls l r r r l js l r r5.r l j l ( , , nr , j \ \ , . t in. i ( t ( ! r l , r t l ( ) th, .i i r ( r r , f rnr l , r l I ( i i lhr . i r I r \ r r l .

Prop0sed rel l0d0'uqv 10, in plnntptr tJt t0f l

lh, ( ( r r ' l r5r( , r ! o i t | l , rLr lh( , .s,r . (1 l r i \ . ( , ( , , r , tLr( : . rork in hr. tp i r1 l( i f i j r r r / i r ( ' s 1() rnr t )nr\ . p|1\ l 'k . t ( ( r rs is i ( ,nr ! . r ( l Inpl . rx, I l \ t , ! f r r r' :hnl | ' r 's r \ f . '1r . r fs Lre( l s( 'n ' r r . ' f i / . r l by ( l r l r i t inf , r pR)p{rscrt I r r l t j ( t r1t ' t ,s \ l ( ) f i . tn! l | ( in i t SI , ( ' t t r ts,s t i \ ( .n l r f t ( ) ! \ . r r r r l f f t t r ( , \ , l i ( ,Us.Lrb ln.r( l ing5 whi( h . r l .1t()r i re t i t css.r l l r . r t \ t r , f ! in { t r ( , pro(. :s

Beview quality managemenl systems' Ihe 'qnnl i tv nrt l ls ' of lhe org.ni /n i (nr h.s n( j I \ ! r r ing t , r t tx,possi l j li t \ ( ) f help bf ing ot \a lLrc I ( (npnn\ nr.r , , or nr . r1 rhL h.rr t l ,qL,r t i t lt robl(ms' , in r .y o\ ent i t r ! i l d1\ \ , . !s bcn.fr t f rom .r r ( , \ i r \ ! ot s. t ! i t i t \nr .nagcnr( 'n i svste 'ns. lh, , i j rst n)rmnt sn' t shoLrtd t r r n r ! f i f | 1) | l l , r { .

*tI 186 51Jr stLr p o, pss Lonl ot

ot thf obj( , r l l lcs, pr( , I ]Lrnm(,of rvork, ! |ung and fcpofrrng nrrrch-| , i ,n ' . l \ ,hn| , r , r , . , r , . ' f . r , , . t , i t r . Inr . . . . . , r r r , i i r r - , . . r , . . , 1t , , .i lL L\ I , i t r . \ r - i . . t r r1. l i h r t . r ! In r l t . r . . r . . . l . r r r . .m,,r . l. r . r r ' . J . r i . rJ . r , t r , , r , i t \ , . r , . , . r t

. . . , . . , , i r , / . . . t . t , , r t .nr . r , . rH,L1,,r . i r ' - i r . r r \p r i . , a i , . t , t , t . r , t r . . r t r t \ iJr- , r . . 1,( .. r , \ i j \ . . , . . t \ , . . t i , . . . t L i . . t . r . r \ \ i t . r . .n\ I . . , , . . t1 r , t , \11 , , . , l r . l, \ . \ , r . , . . r1.L, t . r .a ' , , t , , , ,L ' . /

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. \ rs l r r t d( j thcv rcfr1, \cnt t l t , tnr , .Usi(ncfrrr ' l l l i . r , , 'J , ,

. , . l , . r , r r r . r , , r . r . r r . . , l . r , . t , . , . , r . . , r j , , r . r t , . ,La.1,"

, , , , , . ' . : . , . . . . . .$, , t , . r r 1r1 r . . r r , , . r ' rh. i r . , r , r . . \ l' r , r . , , , i r , , . t i . . . , t , . , t , . , t . , t , . . . , . , t . , t , r , . , t , , i . . t , t , . t , . t , . . t r t \| ) srN r . . ofr t i l l / , , r ( )n\ th.s l r r , i r i ( . r t ion!h() ! t l t , lcrr ibcirrr . lcqLr.rr i ,d. l , ' i l ! !h.r t h.rs t ( , l ) , . ( i ( )nc, t r ,$, i i l r . r5 r(J oL,{rorr , . . )n i r , \ ! .he(ks.i r \ |c( i i , ! r ( i f t (s i s, i . t r (^! th.r i t rh,rs lJ. .n( I ( i f . . t r t i i t ats0 rr

*tThe mp ementat on ol 9tat st ca process contr0 387\Vhere the.lualitv stairls of .tn organization is pnrticlrlarli, low nnd noreliable records arc a\ ail.tblc, it mr\] provc nc(css.rv kr start the lvLrrkb! d.ria collectron from cithcr boughFh goods/scr!i.f (tr comp.nlvtr i r ( tucts/sen iccs. I h is scnrch lor . ln i . r is , of coursc, only a prcl inurary1o process control. ln somc organilatirnls with !cry lo\\' .lLr.liiy staius,,t m.r! be ]rc(jcss.rrr n) start work on hough-in goods/servj.es i'xcluj \ ( , lv so ns n) l lh r i l r rn thc f in$er intr . rds.

ln lh i ' m.r tor i t ! of c.r5cs thc pf t rb lcms c. tn bc soh eJ onlv b) thcidoPi joooi t rot ter F(, .css conhrr l k ' .hniques. lhcsc h\hniqucs h. \ . be.n lht' !b[ ,ct o i rcnci{Rl cmphrsi5 ihr(ugh(\r t th.

' \ 'or lL l rnLl n.rv i ( , rn]s nrr

! ,mf t imos rn\ c l r tcLl n, .on\ r ' \ ' thc inr f f .s\ i (n thr t th. k\Jrniqu( s .11r)$v. I r r fn( t , ns p() i Ih J (Ni ur l icr , th. h\ hniqLk s I r r \ . b. .n , r \ , r i l , rb lc

P an for education and traininql l r is i \ I lwrys rcqir i rc( l s,hcthcr i t is t (J l iun.h i n.$r nrrnr l l ,mf l s! \t ( , r r { ) r h) nrr in i . r in rr i t r r l )R)!1 . r fc\ is l in*{)nc. 1rr) (n l , , f ( ) fg.rnrz.r t ion\{r , I In in ing is Us( lu l i rx l prol i l , rb l r onlV when i l is l ior t ( . | l lo the tcclrr i . r l pfocfsscso.thosc(Jf r tssLrppl icrsnn. l ( rst ,Jnl(Js l d!c.r t ion Drusl'1,r . r l lh( l ( ) l ) ( ) f ihcorgnni^t(nr. Ih( n.r)Unl of t i I ] r ( sp(rr l I f . r l r r ) lt . . l i fgc, lor e\nmf lc, \ ! i lh t fot , r . t .ep.rrnt l (nr nn. l q( | . r l i i ie( l t ( { ( lus,, r shon l f . r in ing fn)gf , rnrnrr c,r f :

Inr ! idc n g(r ! l i f l ( \ l r r l (n l ( t r senior nr.r r rngcr f r , t r rs l i l ( ) . r int , l (ihfnr 1o in i l lnt( .n.d lo l l ( , r ! up w1)rk $ j l l r in th( i r ( \ f f or{r i /n l l ( r r? ( ,t ( , \ ' rdf n g(n)d introclu. t r , f t ( , r r r r r ld l r r r . r r lgf ts crx,uglr t ( ) . ' r rb l {ih(m to lo l lo\{ op nnd {rr . ( \ r fngo rvor l wi th in thcir t lonr.r i r r , r , rI r i l qLrnl i t \ , ru i rS(fs on dx r i rht r ( r ( l g ive t l i fDr t l r ' l r ( fn l ivc t ( lJLr lhcf lhr i f s lLrdi( s c i l l r ( r bv s!pefvi \ ' ( l , i r nnsupcrvisr( l st ! (1\r o ll fn n the pe()plc nnd p() \ ' id i ' lh(nr $ r th . rn nd. 'qu.r t ( '

' rnd( rs l rnr l i r rg() I thr l f fhni( lLrcs so th( i r nr .v usr lhfnr ! f i ihoLrt . r s( .s( o l ,n! stk luc.

Follow-up education and traininglor tho cont lnLred suc.essful ur. 'of Sl 'C, al l edLrcnt l( ,n nnd i fninintnrrst b( ' i i ) l lo\^, ' .1 up during thc introduckJr) pcr iod. I r( t l (nv up cant.rki ' .n\ , forms ldc. l l \ r .n in housc o\pert vvi l l provide the lerdlhrough tho dfsiSn of impk'mentai ion pft)gr.mnr( 's Thc most sat isfa.torv straiegv is k) s i . f t sm,1l l and boi ld Lrp.r b.r fk oi knor ' lc. : tge, lnde\perience. Techn!ues should bc nrtrodLrced alongside eristing m.'th(trlsoi prc.ess control, if thel' exist. lhis allo{'s.omparisons to bc nr.rd|between the ne$, and old methods. When c(rnficlen.c has becn built uptrom these comparisons, the SPC teclurques \^'il] almost take o\er thf.ontrol of the processes ihemselves. Improvements in one or i\,ro arers

&! :aa S 1a t istrca I P roce ss Control

ot t l rc orsrnrz.t ion's oper. t i ( )ns usinE thjrl ish thc tc.h| iqL,es is r . , t i . rbk,nldhols f , r f

ippronch wi l l qLr icklr cst.bun.tcrsi indlng,rn.t

.ontrol

Tho.rulhln and his cl)|c.rgues hn\ | ii)rnxl thr r nn(,ihi,f slrc.csstri fornutnr, l r I

' l , , \ . . l r . nrr , , . , . r . , , . t . . ,F t . , , , \ \_.r f t . r . t , . t . ,n. t , \ , . r t . . r .1.5r\ l ' r . r \ , .1r , , . , , r r . , i . r

xIThe mp emental on of s la l is l ica pr0cess conlrol 389

assessed .s attributrs and !vh!'n nleasurcd as variables. Onc the capabil'iw of the process is knosn, it can bc conpan'd with the requircments.Such comparison will shot\ $rhcihcr thc process can achieve the pro.essor scrvice rcquiremc'nts. Whcl1r thc process is adequate the process capibilitv data .ar1be uscd to sci np conirol charts for future process conholand data recording. {4rere the process is nlcapablc, thc basis is Laid for arational decision concernnrg the requircd nction - thc rcvision of thcrequirements or revisir,l of thepr(ress.

l \ ,4ake use 011he data on the processlhis mlry bc cumulatcd, provide fecdback, or refined in some w.ryCuslrm tcchniqucs for thc idcntificatnrn of either shori or lont trrm.hangcr can gilc vitnl hformain)n, not onlv for process control, butrls() f()r fau lt finding .rnd ftr turc' pl.rflnint. rhc fccdb.rck of process dat,r.rr.rblcs rrmcdi.rl nctnnl to bc plnnnc.l .nd hrki'rr this lvill result in' tcndy improvrments ovcr t ime b both procoss control nndpl1duct/sorr ico qui l i ty. As thc conformancc b rquircment improv( s,ih. dnt.r . in be f t ' f inrd. ' lh is may f t lu irc c ' i thor gft ' . tor prccision in

'n.rsurenlcnt or lcss frcqu('ni intervcntion for colloction. Thc rcfinc

mlrt of ihc dxt i must bc d i r .ct .d h)r i r rd thr coni inuing improvi 'm( 'ntol ihc pn)ccss( s nnd pr)duct of sc'r ! ' ice consistency.

A f inal comment.\ good qu.rlitv manaBonrent systenr providcs .r found;rin)n fof ihc suc-.ossful . rppl i . . r t l (D of SPC tcchniqucs. I t is not p,)ssibh h) 'gr.r f t 'SI 'Conto n poor systom. Without wcll-undcrstrx)d procedures lirr the opcr-rti(,r of proccsses, n$pcction/tesi, nnd for the re.ordin,t of data, SPC

Many organizations would benefit from the implcmeniation ofstaiisiicalmethods of procss conirol and the undorstanding of variation thisbrinBs.lhe systematic structurd approach to their introductj(tr1, whichis recommended here, provides a poh'erful spcarhcad with which k)improve conJormance torequirements and consishnce ofproducts andservices. Increased knowledge of process capabiliiy will also assist inr"drLFl inf , Je. i - run- .rnd nrodu, t

'ert | ' , dc- 'qn.

Thc importance of the systematic use of siaiistical methods of process.ontrol in all typcs of activity cannot be over mphasized. To competeinternationally, both in home markets and overseas/ or to improve costcffccfiveness and efficiency, ortanizations must continue to adopt a pro.lessional approach to ihe collection, analysis and use of process datd.

&t 390 Slatrstrcal process Conlrol

sI Ackn owled gem ents1" " , , . , , , , , ' . ' t r , . . r , . , ( r , ,*r , , . . : , ,n, . , . , . , r , . , r r , . . r . . , t , r tn, \j , ' , , , ' , , , " i , , r ,n. . l .n, ih- . , . . . , . . , t . , , . . , . . , , . ,ht . , . , r , , . ,* , , t r . . , ! , , t . , . ,tnr pft p,rr.rrrorr (rf this. h.plef. rr is rhe out.om,, , ,r

",".1, *"^,1,1|" i ,or. t i !c u1,fk in l r . l l ) ing (r-gnfrz i l iorr to o\ . r .c( jDr( , Lh(, b . i r rs h),r . (cPt.r f .c ol sJ)C

.rrr( l i rDPr)!1, fo lonl . rn.r

sr Chapter hightights

t . , ! . ,1, , , , , t t r . , r . r t . , , , . , . , . . , , , . t , . , . , I' , i r r . r t , r . r i i . |h. t . . ; . . , , r , , , ! . i , , t . . . , . . i . r , . t , , t . , . r . r . , t . , r , . . r . t , .

. ' t r 'LL, l c l \ r r l r , 1. , r , .1 1, , t . r , .

l l l : : l l , ' r,r: l ' r ' ," ' '. :1. : , " . . ' l l " , , r

, , . , , , , .hr . . r . i , . , . , , , , , r1 i , r r , . . i

, \ l r r ) t r \ $ | r r , r L r [ . I r , r j t5( i ( ! . \s i ' r t us(,rs, , r St( .h,r \c, typi{ , r th, LorrJ l i Ic{ l t r r )wt( , ( ls( , . r1) l ( ,iiJ lt iltltlt,ill'ljll; |litill;,,:iliiili;:li ",, ,'".r, ^, '".r '* i,', ,,si , ( in l r \ rL,(r i ( in. . r , r ( r . , ; , . , i ; , . . , ; , , i , , i . i ; , ' , , " "" tskJnir ' 'nPP'r"hr{r, r,.,,,., ,. ,, si,i: ,, t.i"';;;,;.;,::, :lii:ll,;l :lll, ilill,llilillll lil:

" I ' . | | , , t \ r . , , t , , t . , r , . ,1, , f f . , , . r . . t ,1, \ . t . , , t . , , r , . .

. , , . r . , , t , , . t , . . r , . , , r t , , , , . ( . 1{ . , ' , , . r . , t . , r .1. . . , , .1 . , , . . r . t . . , , t ,

. , r , , I: "

, l ' r . , - t l . . . . . . i I a1, . , r i i . r , . r t , r , . , . . , r . r . r t ,

l r . i . ' , . r , . \ ' . " '

. " , " . , ' . , , t . . , , , . r , , r , . . t , r ; r ,

'1 . ,1", 1, . " r r , , . , , r | | . . , r1. i r ,L, ." , . .

.1."1 t l l l , l l , . i , . , r . . , , , , ' . . r r . . r r ._.n.rrr , . , , . , . t . . r . , . i r . . , { r .t , r . ' . i , i , , , r " . t . . , , , t ,1r . . , , . , , r , . . . t . , , t . r , . t " . . , , . . . t , , . , t . r , . . , . . , r . .

J)n{$s. . ' f . ' l r r t res.rn!1 nr.rk( Us(.oi ( t . r l , r 1, I r t r I ro. .ssr\ i t ( r ( ,d nrJn.t( j r r ! l s \sn,nr f f (^. i ( l .s n j r sLr. . .ssirr l, , r . t

r , . " ' , - r ( l ' r r . . t r . , , , , , " , r . . . t r r , . r . . , r ,F. , . , ,u. , , ,11

r r r ' , i , rst . r i l , , : , , . , t l r . r , . , , . . . r , . , , , r , , i , I l , r , i , " ! . , , . , , I LLrer\r ' r i r ) r i ) f ( ' \ . ( l p( , f i i ) fnrnn(.

&r Beferences and funher reading"1il;"1;,,lllilill.'ii liilii,:llfi Jlt"^, /r,fis .,',/,1 ,;, \.,